Donati, Giovanni Battista (jōvänˈnē bät-tēsˈtä dōnäˈtē) [key], 1826–73, Italian astronomer, b. Pisa. Serving as director of the Florence Observatory from 1864, he was a pioneer in the spectroscopic study of the stars and the sun. Donati was the first to obtain and analyze the spectrum of a comet, concluding that the composition of comets is, at least in part, gaseous. He discovered (1854–64) six new comets, among them Donati's comet, which he first saw on June 2, 1858.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.